Effects of lysolecithin supplementation in low-energy diets on growth performance,nutrient digestibility,viscosity and intestinal morphology of broilers

1. The study aimed to investigate the effect of lysolecithin supplementation in low-energy diets on growth, nutrient digestibility and intestinal mucosa characteristics of broilers.

2. A total of 800 one-d-old Ross 308 broiler chickens were assigned to 4 dietary treatments consisting of 10 replicates of 20 broilers each. Broilers were fed with 4 different diets: (i) HE: positive control group broilers received a diet with unaltered energy; (ii) LE: negative control group broilers received a diet with lower energy of about 0.27 MJ/kg; (iii) LElys500: broilers received a diet similar to LE supplemented with 500 g/tn lysolecithin product (Lysoforte Booster Dry^TM); and (iv) LElys300: broilers received a diet similar to LE supplemented with 300 g/tn lysolecithin product. The experimental period was 42 d.

3. Body weight gain in treatments HE was higher than LE during the overall experimental period, while LElys500 and LElys300 had intermediate values. Feed conversion ratio was lower in HE and LElys500 than LE group, while the LElys300 had intermediate values. Fat digestibility was improved in both LElys 500 and LElys300 compared to the HE group. Apparent metabolisable energy (AMEn) was higher in HE, LElys500 and LElys300 than LE. Ileum viscosity at 42 d was also affected, being higher in LE group compared to HE. At 28 d mucosal thickness was lower both in LElys500 and LElys300 compared to HE and LE, while no difference occurred between treatment proliferation patterns of duodenal epithelial cells.

4. These findings indicated that lysolecithin supplementation at 500 g/tn of feed in low-energy diets maintained broiler performance. Supplementation of reformulated low-energy diets induced an increase in digesta viscosity. Lysolecithin supplementation resulted in variable alterations in the duodenum mucosal morphology.     

Influence of graded levels of meals from three lupin species on growth performance and nutrient digestibility in broiler chickens

1. This study investigated the effect of different levels of seeds of lupin species (Lupinus angustifolius, Lupinus luteus and Lupinus albus) on broiler growth performance, nutrient digestibility and apparent metabolisable energy of poultry diets.

2. A control diet containing corn–soybean meal and test diets containing 50, 100, 150, 200 and 250 g/kg of three lupin species were fed to broiler chickens during a 35-day study period. There were 10 replicate cages of 8 broiler chickens per treatment.

3. Growth performance of the birds fed with yellow and white lupin diets was found to be similar to that of the birds in the control group. The use of narrow-leaved lupin seeds in the diet quadratically decreased the body weight gain of birds and increased feed conversion ratio during all the experimental periods (0–14, 15–35 and overall 0–35 days of age).

4. A significant interaction between lupin species and their inclusion levels for apparent metabolisable energy and apparent ileal digestibility of starch was observed, showing a negative effect of increasing levels of narrow-leaved lupin. Pearson correlation coefficients demonstrated that the presence of raffinose and non-starch polysaccharides is a key factor affecting the nutritive value of lupin,

5. Yellow and white lupins could be utilised as an alternative ingredient for soybean meal in the diet of broiler chickens without any adverse effects on growth performance. The narrow-leaved counterpart diet reduced broiler performance, and hence did not provide a satisfactory outcome.     

黄芩黄酮对肉仔鸡营养物质消化率和生长性能影响

探讨黄芩黄酮对肉用仔鸡主要营养物质代谢率以及生长性能的影响。选择1日龄AA肉仔鸡500只,随机分为5个处理,每个处理5个重复,每个重复20只,分别在基础饲料中添加0、5、10、15和20 mg/kg黄芩提取物黄芩黄酮,试验期为49 d。测定各组营养物质代谢率和生长性能指标。结果表明,在0-3周龄,黄芩黄酮可提高肉仔鸡干物质和表观代谢率,3-7周龄,肉仔鸡干物质和表观代谢率降低;在3-7周龄,粗蛋白和粗脂肪代谢率最高的是20 mg/kg黄芩黄酮添加组,分别比对照组提高4.47%和2.12%,差异不显著(P>0.05);在0-3周龄,黄芩黄酮对钙的代谢影响显著(P<0.05),效果最好的是10 mg/kg黄芩黄酮添加组,比对照组提高17.32%,对磷的代谢影响不显著。10 mg/kg黄芩黄酮添加组可明显提高肉仔鸡49日龄平均体重、平均日增重、并降低料肉比(P>0.05)。由此可知,饲料中添加适量的黄芩黄酮在一定程度上可以提高肉鸡对营养物质的代谢,增加对钙的吸收,降低料肉比,提高生长性能,其中10 mg/kg添加量效果较好。     

低能日粮添加木聚糖酶或复合酶对肉鸡生产性能和养分消化率的影响

试验旨在研究肉鸡低能日粮中添加木聚糖酶或复合酶对肉鸡生产性能和养分消化率的影响。采用单因子的试验设计,试验分6个处理,每个处理8个重复,每重复10只肉仔鸡。6个试验饲粮处理分别为正对照组(PC)、负对照组(NC,在正对照组基础上降低表观代谢能836 kJ/kg)、以及4个在NC基础上的加酶组(分别为处理1:木聚糖酶添加量为4 000 U/kg饲料;处理2:木聚糖酶、α-淀粉酶和蛋白酶分别为300 U/kg、400 U/kg和4 000 U/kg饲料;处理3:木聚糖酶、α-淀粉酶和蛋白酶分别为:1383U/kg6、7U/kg和667U/kg;处理4:木聚糖酶、α-淀粉酶和蛋白酶分别为2 766 U/kg、134 U/kg和1 334 U/kg)。试验结果表明,与PC相比,NC降低了肉鸡的增重、提高了料肉比(P<0.05);与NC相比,4个加酶组提高增重3%~10%和改善料肉比2%~8%(P<0.05),加酶后NC组肉鸡的生产性能达到了PC水平。NC降低了干物质、粗蛋白和能量的表观消化率(P<0.05),加酶组对养分消化率具有提高作用,且达到了PC水平;木聚糖酶和复合酶两种酶制剂对肉鸡生产性能和养分消化率的影响差异不显著,处理3和4两组间差异不显著(P>0.05)。结果表明,在降低代谢能836 kJ/kg的肉鸡饲粮中添加木聚糖酶或复合酶,能够使肉鸡的生产性能和养分消化率得以补偿,低能负对照饲粮加酶后能够使肉鸡的生产性能达到与正对照组相同水平。     

植酸酶、柠檬酸和碳酸化合物酶对肉鸡生长性能和养分利用率的影响

文章旨在研究低磷、低钙水平日粮添加植酸酶、柠檬酸和碳水化合物酶对1~21 d肉鸡生长性能及养分消化率的影响。试验选择1日龄肉仔鸡576只,随机分为6组,每组4个重复,每个重复24只鸡。试验共分为6种日粮,阳性对照组日粮(正常钙磷水平)、阴性对照日粮(低磷、低钙)、阴性对照日粮+600 IU/kg植酸酶,阴性对照日粮+600 IU/kg植酸酶+5 g/kg柠檬酸,阴性对照日粮+600 IU/kg植酸酶+500 mg/kg复合碳水化合物酶,阴性对照日粮+600 IU/kg植酸酶+5 g/kg柠檬酸+500 mg/kg复合碳水化合物酶。试验共开展21 d。结果显示:阳性对照组肉鸡日增重和采食量显著高于阴性对照组(P<0.05);植酸酶组添加碳水化合物酶较单独添加植酸酶组显著提高了肉鸡的日增重(P<0.05);植酸酶+碳水化合物酶较阴性对照组显著改善了料肉比(P<0.05)。阳性对照组较阴性对照组显著提高肉鸡胫骨灰分含量(P<0.05);植酸酶组显著提高了总磷、有效磷和植酸磷的回肠表观消化率(P<0.05),同时植酸酶组添加柠檬酸或碳水化合物酶进一步提高了总磷和植酸磷的回肠表观消化率(P<0.05)。阴性对照组添加植酸酶显著提高了表观代谢能及干物质、总能、氮和总磷的表观沉积量(P<0.05),而植酸酶组添加碳水化合物酶提高了干物质和总磷表观沉积量(P<0.05)。结论:在本试验条件下,低磷、低钙水平日粮添加植酸酶和碳水化合物酶改善了肉鸡生长性能、提高了营养物质的消化率和沉积量,而植酸酶日粮添加柠檬酸可以改善营养物质消化率和沉积量。     

Influence of feed form and conditioning time on pellet quality,performance and ileal nutrient digestibility in broilers

An experiment was conducted to investigate the effects of the feed form and conditioning time of pelleted diets on pellet quality, broiler performance and nutrient digestibility during the starter phase. A total of 480 male Cobb broilers were distributed according to a completely randomized experimental design into six treatments with eight replicates each. Treatments consisted of a mash diet and five crumbled diets submitted to different conditioning times (zero, 60, 80, 100, or 120 seconds). The broilers fed pelleted diets submitted to steam conditioning presented higher feed intake and BW gain (P ≤ 0.05), higher coefficient of ileal apparent digestibility (CIAD) of DM and CP, as well as higher ileal digestible energy (IDE) (P ≤ 0.05) than those fed the mash diet. However, treatments did not influence FCR or starch digestibility (P > 0.05). Feed intake increased linearly (P ≤ 0.05) with conditioning time while a quadratic response (P ≤ 0.05) was noted for IDE. Conditioning time did not affect the amount of intact pellets or protein solubility (P > 0.05), but increased pellet durability index (P ≤ 0.01), pellet hardness (P ≤ 0.05), and water activity (P ≤ 0.05). It was concluded that feed physical form and conditioning time influence the performance and nutrient digestibility in starter broilers. and that increasing conditioning times promote better pellet quality.     

Nutrient digestibility,but not mineral absorption,is age‐dependent in cats

Availability of nutrients is influenced by extremes of age, and a better characterization of this influence is necessary for appropriate development of foods and nutritional management throughout life stages of cats. This study investigated nutrient digestibility, mineral absorption, faeces and urine production in three groups of six young, mature and old cats fed two diets containing different energy densities. Apparent digestibility and mineral absorption were calculated by total collection method and values were tested with anova and regression analysis. A quadratic relationship was detected between age and digestibility of dry matter, organic matter, crude protein, acid‐hydrolysed fat and starch in the low‐energy diet. Starch digestibility showed the same response in the high‐energy diet. Young adult cats had intermediate digestibility, mature cats the highest and old cats the lowest. Mineral absorption (calcium, phosphorus, magnesium, sodium, potassium and chloride) and urinary pH were not different among groups. These findings confirm previous studies that found low digestibility of nutrients in some old cats, and support evidence that this trend is even more important in less digestible dry foods. On the contrary, data suggest that mineral formulations do not need to be varied in diets for adult cats of different ages.     

高剂量植酸酶对肉鸡生长性能和消化率的影响

文章旨在研究植酸酶对1~42日龄肉鸡生长发育的影响。采用完全随机试验设计,试验共分为5组,每组6个重复,每个重复24只鸡,各组分别为阳性对照组、负对照、负对照日粮+1000、2000和3000IU/kg植酸酶,试验结束后测定各组对骨功能、骨质量和血液矿物质的影响。随着日粮植酸酶添加水平的升高,显著改善了1~21d肉鸡日增重、采食量和料比(P<0.05),而1~42d肉鸡生长性能表现为显著二次曲线效应(P<0.05),其中负对照组肉鸡日增重和采食量最低(P<0.05),料比最高(P<0.05)。对照组较负对照组显著提高了42d肉鸡胫骨干物质含量(P<0.05)。随着植酸酶添加水平的升高,21d肉鸡血钙浓度表现为显著线性降低(P<0.05),而血磷浓度先升高后降低,负对照日粮+1000IU/kg植酸酶组最高(P<0.05)。42d肉鸡血磷浓度随日粮植酸酶水平的升高表现为二次曲线效应。对照组和负对照组较处理组显著提高了42d肉鸡血钙浓度(P<0.05)。与对照和负对照组相比,负对照添加植酸酶组显著降低了矿物质回肠表观消化系数(P<0.05),而负对照组+3000IU/kg植酸酶较对照组显著降低了能量回肠表观消化系数(P<0.05)。植酸酶在回归分析的基础上提高了肉鸡生长性能,添加高剂量植酸酶3000IU/kg显著提高21d肉鸡日增重。试验为期42d,日粮添加2000IU/kg植酸酶对肉鸡的增重和饲料转化率效果较好。     

Dietary N,N‐dimethylglycine supplementation improves nutrient digestibility and attenuates pulmonary hypertension syndrome in broilers

N,N‐dimethylglycine (DMG) is an intermediary metabolite in cellular choline and betaine metabolism. The present trial aimed to evaluate the effect of dietary DMG on nutrient digestibility and development of pulmonary hypertension syndrome in broilers. A total of 64 14‐day‐old broiler hens (Ross‐308) were raised until age 40 days under cold environmental temperature conditions (15 °C) and were fed a high energy feed in order to incite pulmonary hypertension. Birds were randomly assigned to two groups of which each group had eight replicate pens of four birds each. Test diets contained 0 or 167 mg Na‐DMG (Taminizer^® D; Taminco N.V., Ghent, Belgium)/kg feed. N,N‐dimethylglycine supplementation resulted in a significant improvement in apparent faecal digestibility of crude protein and nitrogen‐free extract. Further, fulminant ascites was numerically lowered by DMG and incidence of pulmonary hypertension decreased significantly from 44.8% in the control group to 14.6% in the DMG group. Finally, fasted plasma level of non‐esterified fatty acids (NEFA) was twofold in the control group in relation to the DMG group. In conclusion, these data demonstrate beneficial effects of DMG on digestibility of non‐fat fractions, on fat metabolism and on progression towards broiler ascites syndrome.     

Physiological stress in broilers: Ramifications on nutrient digestibility and responses

Physiological stress is one of many concerns facing the modern broiler producer. Research has yet to reveal mechanisms that would allow the producer to efficiently minimize the detrimental impacts of physiological stress on broiler performance. One possible approach for improvement in this area is to elucidate the effects of different nutrient regimens on stressed broilers. Sufficient prior knowledge of the effects of stress on metabolism and nutrient digestibility, as well as effective stress induction models, is essential to any researcher interested in delineating the effects of nutrients on stressed broilers. This review examines the physiological mechanisms that activate and control stress, as well as the effects of stress on immunity, metabolism, and broiler performance. Validation procedures for stress induction models are also examined. Additionally, this review examines available research focused on amino acid digest-libility in the presence of stress, digestibility assays necessary for this research, and nutrients that have been shown to have the potential for stress reduction or amelioration.     

Effects of dietary mannanoligosaccharide on growth performance,nutrient digestibility and gut development of broilers given different cereal-based diets

A feeding trial was conducted to evaluate the effects of mannanoligosaccharide (MOS) on the growth performance, nutrient digestibility and gut development of broilers given a corn or a wheat-based diet over a 21-day experimental period. Dietary MOS improved the growth performance of birds given the wheat-based diet compared to that of birds given the corn-based diet during 7–21 days of age. In line with this, the ileal digestibility of starch was increased by MOS at 21 days of age. The addition of MOS modulated the development of gut microflora. From day 7 to day 21, the numbers of mucosa-associated coliforms along the small intestine were decreased; whereas the numbers of mucosa-associated lactobacilli were increased by MOS, regardless of the cereal type in the diets. Dietary MOS also reduced the counts of coliforms and Clostridium perfringens in the caeca of birds by 21 days of age. Villus height at the jejunum was not affected by MOS but the crypt depth and the muscularis thickness were reduced. The specific activities of maltase and alkaline phosphatase were increased in birds given the MOS-supplemented diet; whereas the development of leucine aminopeptidase was delayed by MOS. All these changes in the mucosal morphology and function were dependent on the type of cereal and/or the age of the birds.     

Amending reduced fish‐meal feeds with marine lecithin,but not soy lecithin,improves the growth of juvenile cobia and may attenuate heightened responses to stress challenge

Sparing of marine resources in aquafeeds can be environmentally and economically advantageous; however, fish meal (FM) replacement can affect the production performance and physiological competence. Phospholipids are increasingly understood to be involved in maintaining growth and vigour in fish and may be deficient in reduced FM formulations. Accordingly, we evaluated the growth and stress tolerance of juvenile cobia fed typical (50% FM) or reduced FM feeds (12% FM) with or without phospholipid amendment [1% marine lecithin (12% FM + Marine PL) or soy lecithin (12% FM + Soy PL)] for 6 weeks in triplicate tanks (N = 3) in a recirculation aquaculture system. The 50% FM feed yielded significantly superior growth and growth efficiency in comparison with the 12% FM and 12% FM+ Soy PL feeds, but the 12% FM+ Marine PL feed yielded comparable results to 50% FM feed. A low‐water stress challenge induced elevated plasma glucose, cortisol and lactate levels in all treatments. However, a significant interaction (diet × stress) effect suggested a lesser cortisol response among fish fed the 12% FM+ Marine PL and 50% FM diets. These findings demonstrate that growth performance and, perhaps, resilience of cobia raised on reduced FM feeds may be improved by the addition of marine‐origin phospholipid to the diet.     

不同复合蛋白酶对肉鸡生长性能和营养物质利用率的影响

为研究添加不同复合蛋白酶制剂对肉鸡生长性能、屠宰性能和营养物质利用率的影响,试验选取2592只1日龄罗斯308商品肉仔鸡公雏,随机分为6个处理组,每个处理组12个重复,每个重复36只,饲养密度12只/m^2。处理1组为对照组,不使用酶制剂,日粮蛋白水平相对于营养标准降低了1.5%,处理2~6组在处理1组的基础上添加5种酶制剂,试验期38 d。结果表明:肉鸡13~24日龄,添加不同蛋白酶均在不同程度上有改善肉鸡料重比的趋势(P<0.10),其中T2组效果较佳,料重比改善0.017;其余阶段及全期,不同处理的肉鸡生长性能无显著差异(P>0.05);各处理组之间肉鸡全净膛率、胸肌率、腿肌率、翅重率、腹脂率、肌胃率、腺胃率差异不显著(P>0.05);在低蛋白日粮的基础上添加蛋白酶均可提高肉鸡日粮表观代谢能(AME)、氮校正表观代谢能(AMEn)、能量利用率以及粗蛋白质表观消化率,其中AME分别提高19、33、8、61、51 kcal/kg,能量利用率分别提高1.2%、1.3%、0.5%、2.2%、1.8%,但统计上差异不显著(P>0.05)。综上所述,在本次试验条件下,添加不同外源蛋白酶对肉鸡生长性能和屠宰性能无显著影响,但可在一定程度上提高营养物质利用率,从而降低肉鸡粪便氮排泄量。     

复合酶制剂对仔猪生长性能及养分消化率的影响

研究选取了体重为20.0 kg左右的杜×长×大三元杂交猪24头,随机分为3组,每个处理组8头,分别饲喂不含酶制剂、含酶制剂Ⅰ、含酶制剂Ⅱ的3种日粮,饲养期为28 d。结果表明,酶种类齐全、酶活高的复合酶制剂,能够更有效地提高仔猪的生长性能,改善对饲料氮和磷的利用,降低粪便的排放污染,是未来高效新型环保饲料添加剂的发展趋势。     

黄芩多糖对肉仔鸡营养物质消化率、生长性能的影响

用黄芩多糖作为饲料添加剂,研究其对内用仔鸡主要营养物质代谢率以及生长性能的影响。试验选用体重相近的AA肉仔鸡120只,随机分成4个处理,每个处理3个重复,每个重复10只。各组基础日粮相同,试验组分别在基础日粮中按100、200和400 mg/kg饲粮添加黄芩多糖;并分别在第3周龄和第5周龄各进行4 d代谢试验,在7、14、21、35和49日龄以组为单位称重、称余料,计算耗料量、日增重和料重比。分别于21、35和49日龄每组随机取3只体重接近平均体重的鸡进行屠宰,采血,制备血清,进行相关指标检测。试验结果表明,在试验添加量范围内,黄芩多糖对内仔鸡养分代谢率具有降低作用,且对0-3周龄肉仔鸡的影响要大于3-7周龄。在3-7周龄,粗蛋白代谢率最高的是200 mg/kg黄芩多糖添加组,比对照组高24.04%,差异显著(P0.05)。200 mg/kg黄芩多糖添加组对内仔鸡体重、日增重和料肉比影响较显著。     

壳聚糖对肉牛生长性能及营养物质消化率的影响

试验旨在研究壳聚糖(chitosan,CHI)对肉牛生长性能及营养物质表观消化率的影响。选择体重、月龄接近,健康无病的24头西门塔尔育肥公牛,随机分为3个日粮处理组,每组8头牛,饲养试验分前、中、后三期,每期28 d,共84 d。三组日粮分别是在基础日粮中添加0、500和1 000 mg/kg的壳聚糖配制而成。结果表明:试验全期500 mg/kg壳聚糖组的平均日增重(ADG)和日采食量(ADFI)最高、料肉比(F/G)最低;日粮添加500 mg/kg壳聚糖可提高肉牛干物质、蛋白质、能量和钙表观消化率。说明日粮中添加500 mg/kg壳聚糖可提高肉牛营养物质的消化率,进而促进肉牛的生长。